Patent ID: 6895940

Claim:
A control system for controlling a plurality of actuator devices in each of which a piezoelectric actuator is installed, wherein each of said actuator devices comprises an high pressure port, a low pressure port and a movement member interposed between the high pressure port and the low pressure port, and is communicated with a common-rail, each of said piezoelectric actuators being deformed according to an amount of energy to displace the movement member between the high pressure port and the low pressure port, said energy being kept in each of the piezoelectric actuators by energization, said control system comprising: means for storing thereon individual data each specifying a condition of the energization permitting energy to be supplied to each of the actuator devices, said energy being required for making each of the actuator devices a predetermining operating state, said condition of energization including a charging voltage of the piezoelectric actuator; and means for converting the individual data into actual data according to a difference between an actual operating condition of each of the actuator devices and a reference operating condition thereof, wherein said actual operating condition of each of the actuator devices includes an actual temperature of each of the actuator, an actual pressure in the common-rail and an actual displacement amount of the movement member, said reference operating condition includes a reference temperature of the actuator, a reference pressure in the common-rail, a reference actual displacement amount of the movement member and a reference voltage of the actuator, and wherein said converting means calculates difference values between the actual temperature and the reference temperature, between the actual common-rail pressure and the reference common-rail pressure and between the actual displacement amount and the reference displacement amount so as to calculate a target voltage by which the actuator is charged according to the calculated difference values and the reference voltage.