Method and apparatus for monitoring injection pressure

A method of monitoring injection pressure applicable to an injection molding machine having a screw adapted to be propelled to fill a resin into a cavity of a mold, said method comprising the steps of:

• (a) storing in advance cavity data of said mold;
• (b) displaying, based on said cavity data, a configuration of said cavity and divided regions obtained by dividing said cavity into a plurality of regions in a cavity display section provided on a display screen;
• (c) detecting a screw position by a screw position detecting means while detecting an injection pressure at said screw position by a pressure detecting means;
• (d) displaying in a graph a relationship between detected screw position and injection pressure in a pressure waveform display section provided on said display screen;
• and
• (e) displaying a screw position region corresponding to said divided regions of said cavity being filled with the resin in a screw position region display section provided on said display screen, in comparison with a coordinate representing said screw position being displayed in said pressure waveform display section.