Injection molding machine and method of controlling the same

A method of controlling an injection molding machine comprising a step of

• adjusting a time difference between a first injection start timing of a first material injected from a first injection apparatus performing an injecting operation of the first material, based on a first injection start signal for the first injection apparatus output from a central controller centrally controlling an injection molding operation, and a second injection start timing of a second material injected from a second injection apparatus performing an injecting operation of the second material based on a second injection start signal for the second injection apparatus output from the central controller,
• the method further comprising steps of:
• (a) generating a synchronization signal by a synchronization signal generator, based on a command from the central controller;
• (b) controlling the first injection apparatus;
• and
• (c) controlling the second injection apparatus,
• wherein the step (b) includes steps of:
• (b1) inputting the first injection start signal to a first controller;
• (b2) inputting the synchronization signal to the first controller;
• (b3) measuring elapse of a first predetermined time from input of the synchronization signal;
• (b4) outputting a first command signal from the first controller to a first servo amplifier after the elapse of the first predetermined time measured in the step (b3);
• and
• (b5) controlling an opening degree of a first servo valve by the first servo amplifier, and
• the step (c) includes steps of:
• (c1) inputting the second injection start signal to a second controller;
• (c2) inputting the synchronization signal to the second controller;
• (c3) measuring elapse of a second predetermined time from input of the synchronization signal;
• (c4) outputting a second command signal from the second controller to a second servo amplifier after the elapse of the second predetermined time measured in the step (c3);
• and
• (c5) controlling an opening degree of a second servo valve by the second servo amplifier.