COMBINATION ACTUATOR Russian patent published in 2005 - IPC

FIELD: control systems for flying vehicles.

SUBSTANCE: proposed actuator has housing with channels communicating with hydraulic delivery and drain lines; hydraulic motor; electrohydraulic power amplifier; servo unit; feedback sensor; spring-loaded lock; servo-unit cross-feed valve; combination mode enabling electrohydraulic valve; backup spool-operated cylindrical distributor built of backup valve and main valve disposed in the latter and kinematically coupled with inlet control rocker arm; it is provided with collar disposed inside bore of backup valve in the form of recesses spaced 180 deg. apart to form two relatively isolated cavities of which one permanently communicates with drain line and other one is brought in communication with delivery line by opening electrohydraulic valve and with drain line by closing this valve; backup valve is locked in neutral position by means of alignment springs; housing also has bore to receive two bushings installed coaxially with respect to valve distributor and provided with two grooves on outer surfaces and with two-step cylindrical internal through drillings accommodating double-collar spring-loaded plungers for displacement; one of these plungers contacts through its butt-end collar of back-up valve and one of butt-ends of housing bore at a time; other plunger contacts stop on outer end of back-up valve and other butt-end of housing bore; two drillings are made in inner bore of each bushing, two of them communicating by means of radial holes of bushings and outer surface groove with delivery line and remaining ones, with backup valve space communicating with electrohydraulic valve; larger collar of each plunger has radial through jet hole on its cylindrical surface and drilling flat both providing communication in one of extreme positions of plungers between drillings of bushings connected to backup valve space and electromagnetic valve and drain line and disconnection from delivery line, and in other extreme position of plungers they communicate with delivery line; in this case radial jet holes of plungers are disconnected from both drillings; in addition housing has spring-loaded check valve affording working liquid passage in electrohydraulic valve-to-backup valve direction and blocking working liquid flow in backward direction; jet-produced fixed resistance is set in channel providing communication between inner two-step cylindrical through drillings of bushings and backup valve space communicating with electrohydraulic valve in section between mentioned drillings and space.

EFFECT: enhanced reliability of control.

1 cl, 3 dwg