Patent ID: 7892463

Claim:
A method for correcting a mold clamping force in a mold clamping apparatus wherein the mold clamping apparatus includes a spring-built-in mold lying between a movable half mold and a stationary half mold, and in which a variation in the mold clamping force, during a production operation, is detected and the mold clamping force is corrected on the basis of the detected variation, and wherein a work load accompanying high-pressure mold clamping of a mold clamping process is used as the variation, which comprises: presetting work load as a standard (standard work load) accompanying high-pressure mold clamping, detecting the work load accompanying high-pressure mold clamping of the mold clamping process (detection work load) during production, and correcting the mold clamping force on the basis of a deviation of the standard work load from the detected work load, wherein the work load is ascertained by integrating the magnitude of load in a high-pressure mold clamping section from a high-pressure mold clamping switching position, which is a preset unchanged position, where the high-pressure mold clamping is started, to a mold clamping completion position in a mold clamping process, in which high-speed mold clamping, low-pressure, low-speed mold clamping and high-pressure mold clamping are sequentially performed over mold position or time, wherein a torque value accompanying high-pressure mold clamping is used as magnitude of the load.