Abstract: A hydraulic control system for an injection molding machine is provided with a pump driving induction motor capable of operating at an operating speed corresponding to a flow rate at which a hydraulic fluid is to be supplied to a desired one of hydraulic actuators for operating the functional components of the injection molding machine to supply the hydraulic fluid efficiently at a reduced power consumption. Since the operating speed of the induction motor is controlled according to the desired flow rate of the hydraulic fluid corresponding to the operating speed of the hydraulic actuator, the hydraulic fluid can efficiently be supplied to the hydraulic actuator and the useless power consumption can be avoided.

Abstract: A totally self-checking checker checks the faults of a logical circuit and also checks faults inside itself. The totally self-checking checker does not require a large number of gate circuits and minimizes the number of test code words that are used. The code words, of the code word sets to be used, are less than half of all the code words of code since the bits of code Y are divided into M disjoint partial sets.