Hydraulic fluidic servoactuators

Claim 1

A hydraulic fluidic servoactuator consisting essentially of: fluid servovalve means including proportional fluid amplifier means comprising a power nozzle, a pair of control ports, a pair of outlet passages, an interaction region, and an isolation chamber between the interaction region and the outlet passages, the isolation chamber having a return conduit connected thereto, said fluid servovalve means further including a position command signal input for receiving a fluid position command signal, a force beam and bellows assembly for summing the position command signal and a feedback signal and producing a fluid control signal indicative of the summation, means for conveying said control signal to said fluid amplifier means for amplification thereby, and output means in communication with the outlet passages of said fluid amplifier means; actuator means in communication with said output means and including a movable member operable to change position in response to fluid signals applied thereto; feedback means comprising a transducer connected to said actuator for producing fluid feedback signals indicative of the position thereof; and means for conveying the feedback signals to the force beam and bellows assembly.