EXTERNAL EXTENSION TYPE PROGRAMMABLE CONTROLLER

摘要

This invention relates to an external extension type programmable controller wherein part of the control functions are made independent externally. This controller comprises a main PMC (programmable machine controller) unit (2) incorporated in a numerical controller (CNC) (1) and controlled on the basis of the instruction of the numerical controller (1), an input/output unit (3) connected to the main PMC unit (2) and transferring signals to/from a mechanical unit A (61) and an extended PMC unit connected to the main PMC unit (2) through the input/output unit (3) and controlling a mechanical unit B (62) with its own sequence program. The extended PMC unit (4) stores by itself the sequence program relating to the mechanical unit B (62) to be controlled and controls the machine by performing transmission and reception of instructions and various data with the main PMC unit (2) through communication means (5).