Error sensitive fluid operated actuator

Claim 1

VARIABLE FLOW LIMITING MEANS FOR CONNECTION IN SERIES WITH A FLUID OPERATED ACTUATOR SO AS TO CONTROL THE RATE OF ACTUATION BY LIMITING THE RATE OF FLUID FLOW THERETHROUGH SAID VARIABLE FLOW LIMITING MEANS COMPRISING FIRST AND SECOND PAIRS OF ORIFICES, THROUGH EACH OF WHICH FLOW FROM A FLUID SOURCE MAY TAKE PLACE, ONE ORIFICE OF EACH PAIR OF ORIFICES BEING A RELATIVELY FIXED ORIFICE AND THE OTHER ORIFICE OF EACH PAIR OF ORIFICES BEING A VARIABLE ORIFICE, THE FLOW THROUGH SAID FIRST PAIR OF SAID ORIFICES BEING A PRIMARY FLOW, AND THE FLOW THROUGH THE SECOND PAIR OR ORIFICES BEING A PILOT FLOW, FIRST AND SECOND PRESSURE CHAMBERS HAVING A PRESSURE RESPONSIVE MEANS DISPOSED THEREBETWEEN, THE MOVEMENTS OF SAID PRESSURE RESPONSIVE MEANS IN RESPONSE TO PRESSURE DIFFERENCE IN SAID CHAMBERS SERVING TO VARY THE FLOW THROUGH THE VARIABLE ORIFICE OF SAID FIRST PAIR OF ORIFICES, SAID FIRST OF SAID PRESSURE CHAMBERS BEING CONNECTED TO SENSE THE PRESSURE DROP OCCURRING ACROSS SAID FIRST FIXED ORIFICE AS THE RESULT DROP OCCURRING ACROSS SAID THE SECOND PRESSURE CHAMBER BEING CONNECTED TO SENSE THE SOURCE PRESSURE, AND SIGNAL RESPONSIVE MEANS OPERATIVE TO VARY THE EFFECTIVE AREA OF SAID SECOND VARIABLE ORIFICE, SO AS TO VARY THE PRESSURE DROP THEREACROSS, THE LATTER PRESSURE DROP BEING COMMUNICATED TO SAID FIRST CHAMBER, SAID CHANGE IN AREA OF SAID SECOND VARIABLE ORIFICE MODULATING THE POSITION OF SAID FIRST VARIABLE ORIFICE TO REGULATE THE PRIMARY FLUID FLOW IN ACCORDANCE WITH SAID SIGNAL CHANGES.