The connection between the components of a DNC system is realized by a data bus. This direct data transmission
makes the conventional data carriers such as punch cards, magnetic stripes, discs as well as the
corresponding recording and read-in instruments unnecessary.
The significant characteristic of the DNC operation is the management and timely disposition of the information.
To be able to calculate and distribute this information to the right position, interfaces are needed.
Through the interfaces all the integrated parts of the DNC net are connected with the master computer. The
master computer is able to calculate machine and production data, switch operation modes, address, read-in
and record the correct storage location as well as automatically transmit them to the machine upstream computers.
Data input and data processing in DNC operation
Through the structure of a DNC system (see figure 70) it is possible to enter data into different devices.
These devices can be located far away from each other.
Small NC programs can be written directly on the CNC machine tool. For writing extensive or complicated NC
programs it is better to use an external programming work station.
A DNC system generally includes the following basic functions.
· storage and management of NC programs
· correct distribution of NC programs to the machines
· re-transmission of the corrected and optimized NC programs from the machine to the master data
storage medium