It's some kind of air hammer, because that electric motor on the top run one enormous beltwheel/balancing wheel in the backside and wheel moves the piston mechanism who lift that 30 kg hammer ram up and down.
I bought it from one other blacksmith almost two years ago and i hear that it's made probably some time in the fifties or the sixties. I found also this text "P. Yeakley, Billeter & Klunz" to right side of it's frame.
There you find other picture of my power hammer. [link]