PURPOSE: To improve the rate of operation of a machine by disposing a magazine mounting previously a plurality of parts in the operation area of a supply robot device to supply parts from said robot device when a part transfer device is stopped.

CONSTITUTION: A magazine 61 mounting a plurality of parts n is disposed at the side of a part supply device 31 in the operation area of a supply robot device 11. The parts n supplied by the part supply device 31 are normally supplied by the supply robot device 11 on an assembling jig 7 moving on a conveyer device 1. If any troubles take place in said device 31 or any mischuck takes place in said device 11, a part supply stopping signal is generated and thereafter said device 11 supplies parts n in the magazine 6 to the assembling jig 7. Further, when the stopping signal is released, the normal supply operation is resumed, so that the rate of operation of machine can be improved.