A revolving nozzle station and a revolving drive device that revolves the revolving nozzle station are housed inside a cassette case of a cassette-type nozzle exchanging unit. In an outer circumferential portion of the revolving nozzle station, multiple nozzles for exchange with a nozzle of component mounter are arranged radially along a revolution path, and the nozzles are held in a detachable manner. A nozzle exchange port is formed in a top end surface of cassette case, and nozzle exchange is performed between the revolving nozzle station and a mounting head of the component mounter through the nozzle exchange port. A shutter mechanism which opens and closes the nozzle exchange port is provided in the cassette case.