Injection molding method using a plurality of control parameters

An injection molding method for molding an article by using an injection molding machine, comprising the steps of:

• commencing, immediately before filling up of the mold cavity with a resin, a control of the injection speed to follow a set value V.sub.0 of the injection speed, starting at a control start point which is determined by a set value or values of one or more of control parameters including mold opening degree, screw position and the injection pressure;
• conducting control of the injection pressure such that the injection pressure is set to a value represented by a set function P=F(t) which provides the maximum injection pressure within a range which does not allow generation of burr and, after the actual injection pressure has been reached the value represented by said set function P=F(t), the injection pressure varies in conformity with said set function P=F(t), while restricting the injection speed to a range which does not allow backward flow of the resin or does not cause the absolute value of backward flow speed of resin to exceed a predetermined maximum allowable value, and setting a command mold opening degree to such a value that allows relief of gases but does not allow generation of burr at the mold parting surface;
• and
• after the command value of the mold opening degree has been reached, switching the control to a mode in which the injection pressure is controlled so as to maintain the mold opening degree in conformity with said command value, wherein the injection pressure is restricted to a range which does not cause generation of burrs.