Introduction:

Customer has plastic injection machines in molds to fabricate plastic pieces for the car industry.The machines' mold can be changed depending on production's requirement, so type and number of fabricated pieces may oscillate.

When the customer contacted us, each machine was handled by one operator. Operator extracts, examines and places the piece, then reads the piece's code from a prepared paper using a bar-code reader. In this moment the workplace's computer prints a bar-code ticket which operator sticks to the piece. All this procedure was slow and generates lots of errors.

System description:

The taken solution was install a PLC (ABB's KR51) for each machine to detect the machine's injection pulses and then tranmit them to an application in the PC, using a easy series line protocol. Moreover, protocol allows to consult internal piece-counters, parameter's modification, etc.

Starting his spell of work, operator indicates what kind of piece is going to be fabricated and it's a new application in the computer which gets the injection-pulse's indication. This injection-pulse's indication is drafted to the PLC and then it prints the appropriated number of tickets.

Operator just examines the piece, places it and sticks tickets.

The system allowed customer to reduce the time of pieces' manufaturing and to increase the production.

Same system was installed in Faurecia-Zaragoza (Spain).

Special version, using SIEMENS PLC (CPU 222), was also developed.