Generally these are single line/stroke fonts for Computer Numerical Control (CNC) machines. Most don't have a specific name or foundry. They simply are supplied with CNC software from the manufacturer.
CNC machines are computer driven cutters/engravers used in manufacturing many items which need to be custom shaped or carved. I suspect signs such as those are carved by machines. Most likely CNC machines, but there is a possibility that laser engravers were used. In the case of laser engravers, any font will work.
You can find several single stroke fonts if you google for "CNC Fonts"