Method for designing a mold, method for producing an injection molding, program and injection molding device

A method for producing an injection molding in the case of implementation of injection molding with a mold having a plurality of resin inflow conduits to a cavity, comprising the steps of:

• determining a mold design parameter in relation to at least one of the arrangement, the shapes and the sizes of said resin inflow conduits, by combining a numerical analysis method for calculating an injection molding process with a computer-aided optimization method for a purpose of obtaining a desired injection molding condition;
• producing the mold based upon the determined mold design parameter;
• and
• carrying out the injection molding with the produced mold,
• wherein said purpose is to obtain a molding condition in which weld line occurrence in a molding can be suppressed or controlled, and
• wherein an area in which weld line occurrence is intended to be suppressed or controlled is divided into a plurality of areas and a weighting weld line occurrence quantity in the plurality of the areas is used as a weld line evaluation value, thereby inducing weld line occurrence into a specified area or avoiding weld line occurrence in a specified area.

An injection molding device comprising:

• a molding device main body that supplies resin material to a mold having a plurality of resin inflow conduits to a cavity, through said resin inflow conduits;
• a memory section that memorizes process parameters determined by combining a numerical analysis method for calculating an injection molding process and a computer-aided optimization method;
• and
• a control section which controls said molding device main body based upon process parameters in accordance with the mold to be used, and carries out injection molding by controlling time-sequentially an inflow of the resin material from said resin inflow conduits to said mold,
• wherein said purpose is to obtain a molding condition in which weld line occurrence in a molding can be suppressed or controlled, and
• wherein an area in which weld line occurrence is intended to be suppressed or controlled is divided into a plurality of areas and a weighting weld line occurrence quantity in the plurality of the areas is used as a weld line evaluation value, thereby inducing weld line occurrence into a specified area or avoiding weld line occurrence in a specified area.