Plural channel servo systems

Claim 1

A SERVO SYSTEM COMPRISING A PLURALITY OF SUBCHANNELS HAVING A COMMON INPUT TO WHICH A DEMAND QUANTITY MAY BE APPLIED AND SEPARATE OUTPUTS WHICH ARE REQUIRED TO BE IN SUBSTANTIAL AGREEMENT, THERE BEING A MEMBER WHICH IS POSITIONED IN DEPENDENCE UPON THE OUTPUTS OF ALL THE SUB-CHANNELS AND EACH SUB-CHANNEL COMPRISING AN AMPLIFIER ADAPTED TO PRODUCE AN OUTPUT SIGNAL DEPENDENT ON THE DEMAND QUANTITY, AN ACTUATOR FOR OPERATING THE SUB-CHANNEL OUTPUT AND MEANS FOR CONTROLLING THE ENERGIZATION OF THE ACTUATOR, SAID MEANS BEING COUPLED TO THE OUTPUT OF THE AMPLIFIER, TO THE ACTUATOR AND TO SAID MEMBER AND HAVING TWO CONDITIONS OF OPERATION IN THE FIRST OF WHICH THE OUTPUT OF THE AMPLIFIER IS COUPLED TO THE ACTUATOR TO ENERGIZE IT AND THE ACTUATOR IS COUPLED TO SAID MEMBER TO TEND TO POSITION IT IN DEPENDENCE UPON THE OUTPUT OF THE ACTUATOR AND IN THE SECOND OF WHICH THE ACTUATOR IS DRIVEN IN DEPENDENCE UPON ANY LACK OF CORRESPONDENCE BETWEEN ITS OUTPUT AND THE POSITION OF SAID MEMBER AS POSITIONED BY THE ACTUATORS OF THE OTHER SUBCHANNELS, EACH SUB-CHANNEL FURTHER INCLUDING MEANS RESPONSIVE TO LACK OF CORRESPONDENCE BETWEEN THE POSITION OF SAID MEMBER AND THE OUTPUT OF ITS ACTUATOR TO CAUSE SAID ENERGIZATION CONTROL MEANS TO CHANGE TO ITS SECOND CONDITION IF SAID LACK OF CORRESPONDENCE EXCEEDS A PREDETERMINED VALUE.