PURPOSE: To carry out with real-time the preparation of component parts and the cancellation of the component parts when the component parts become unnecessary, by providing a means for instructing to prepare necessary component parts with real-time in a service center.

CONSTITUTION: Upon preparation of component parts, a worker sets a calling-up reflector 21 on an operation board 29 at a predetermined position after completion of a basic component assembly in order to call up the necessary component parts.Then a calling-up sensor 18 automatically reads the instruction and delivers calling-up signals concerning the necessary component parts to the service center 11, and therefore, the component parts are prepared with real-time at its final processing station by means of an automatic preparation line 13. If any inferior article is detected during inspection process 15, this article is made unable to be shipped. In this stage component parts to be assembled to the inferior article come to be unnecessary. Accordingly, a cancelling reflector 22 on an assembling operation board is set at a cancelling position (NG) at that time, thereby the cancelleration is made possible.