| 摘要 |
PURPOSE:To uniformly apply necessary mold clamping forces over the whole mold by a method wherein a pressure regulating valve is controlled by an output signal sent from a setter by comparing a detection value sent from a detector to detect the inner pressure of a regulating cylinder and a set value sent from the setter setting the mold clamping forces with each other by a comparator. CONSTITUTION:A pressure detector 11 provided din an oil hydraulic circuit 9 is connected to a comparator 12 so as to detect the pressure in a regulating cylinder 8 in order to input the detected pressure to the comparator 12. When necessary old clamping forces in the respective stages during mold closing and mold opening processes are set at a setter 14, under the state that the position of a movable platen is detected with an LS, an encoder or the like, a pressure regulating valve 13 is controlled by output signals sent from the setters 14 in the respective sections so as to be able to give all the regulating cylinders 8 uniform necessary inner pressure. Accordingly, because the respective tie bars 3 are extended and contracted by the regulating cylinders 8 so as to make the tensile force (mold clamping force) or the tie bar 3 constant, the constant mold clamping force can be obtained under absorption of the minute change of the mold clamping force due to thermal influence and the like. |
