摘要 |
An injection pressure is detected as a pressure detection value Dp during injection and filling, and the thus obtained pressure detection value Dp is multiplied by a preset predetermined coefficient so as to be converted into a desired mold clamping force Fc with which the mold clamping force is controlled. The desired mold clamping force Fc is set to a minimum value which a mold does not open, that is, the desired mold clamping force Fc is calculated with the use of Fc=( alpha *S* beta )Dp, where alpha is a charging rate of resin in a mold cavity, S is an entire projected area of a molding article, beta is a safety factor, and Dp is a pressure detection value Dp. With this arrangement, in a section where the injection pressure gradually increases from zero during injection and filling, the profile (variation curve) of mold clamping force gradually increases as the injection pressure varies. At this stage, the mold clamping force during injection and filling is set to a minimum value with which the mold does not open so that the power consumption can be minimized.
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