When a circuit board type for manufacturing in various component mounting machines (35) is switched from a circuit board A to a circuit board B, a replacement robot (45) for automatically replacing cassette type feeders (11) carries out, in parallel with component mounting operations for the final circuit board A before switching the circuit board type, feeder replacement prior to the circuit board type switching wherein the replacement robot successively removes cassette type feeders (11) that are not to be used in the manufacturing (circuit board B) after switching the circuit board type from within the cassette type feeders (11) that have supplied necessary components for component mounting operations for the final circuit board A for that manufacturing during manufacturing prior to switching the circuit board type from a feeder set area (41) of the component mounting machine (35) and successively collects the same in a feeder stock area (43), and also successively removes the cassette type feeders (11) to be used in manufacturing (circuit board B) after the circuit board type switching from the feeder stock area (43) and successively sets the same in the feeder set area (41) of the component mounting machine (35).