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8522821 Torque motor linearization  
A servovalve torque motor includes first and second pole pieces and an armature. Each of the first and second pole pieces includes an armature face that opposes the armature. The area of the...
8322375 Control device and hydraulic pilot control  
A control device for controlling a hydraulic consumer, is equipped with a distributing valve having a control pressure chamber and a control slide that can be displaced against the force of a...
8302629 Valve unit  
A valve unit 1 includes a first valve body 14 which is slidable in a valve housing 11 and a second valve body 13 which is slidable with respect to the first valve body 14, and the valve housing 11...
7631663 Pilot valve  
There is disclosed a pilot valve, especially for a servo valve, comprising an actuating motor and a hydraulic preamplifier via which a control pressure difference can be created that acts upon a...
7458394 Methods and apparatus for mechanically adjusting a null offset in a torque motor of a servovalve  
A servovalve assembly includes a motor having a flapper shaft. A flapper couples to a first end of the flapper shaft such that the flapper shaft orients the flapper between a first nozzle and a...
7093607 Methods and apparatus for maintaining pressure gain in a servovalve assembly  
A servovalve has a sleeve having both a first metering aperture and a second metering aperture in fluid communication with a single port cavity defined by the servovalve. A spool oriented within...
6755205 Method to stabilize a nozzle flapper valve  
A method and apparatus to attenuate a flapper valve from oscillating is presented. An inertia tube is added to the flow path of the flapper valve nozzle, which effectively produces a stabilizing...
6648014 Fluid control valve and plate with filter  
A hydraulic control valve has a valve block provided with a plurality of ports, a valve body formed with ports corresponding to the ports of the valve block, and a plate disposed between the valve...
6367250 Shape memory alloy actuator  
The present invention discloses and teaches a unique, remote optically controlled micro actuator particularly suitable for aerospace vehicle applications wherein hot gas, or in the alternative...
6273135 Fuel flow control apparatus  
A high pressure fuel system includes tapped high pressure flows (22,24) with restrictors (44,46) to provide low pressure flows with which, via a valve (50) to enable either a low pressure flow to...
6227247 Position driven hot gas proportional thruster valve  
A thruster valve has a continuously positionable piston between a closed position and a maximum open position. The piston moves in response to the difference in pressure between the pressure in...
5709245 Optically controlled actuator  
Fiber optics and photovoltaic devices for optically controlling a conventional Electro-Hydraulic Valve (EHV) without need for external wiring. One laser, one fiber and one photocell located at the...
5697401 Hydraulic servovalve  
A hydraulic servovalve controls the direction of flow of a working fluid and a flow rate of a working fluid between a plurality of ports. The hydraulic servovalve includes a spool axially movably...
5533551 Pressure regulating servovalve  
It comprises a distributor body having an output port, a feed port and a return port, and a slider adapted to slide inside the distributor body between a first position isolating the output port...
5244002 Spool position indicator  
An electro hydraulic servo valve has a pair of oppositely polarized magnets mounted in the surface of the spool of the valve to be controlled. A Hall effect sensor is mounted in the housing...
5240041 Synthesized flow-control servovalve  
An improved two-stage servovalve (70) has a pilot-stage and an output-stage. A torque motor (16) produces pivotal movement of a flapper (18) in response to a supplied electrical current. The...
5197516 Hydraulic servo valve with controlled disengagement feature  
A hydraulic servo valve arangement of the type having a hydraulic amplifier followed by a spool type servo valve second stage, includes a deceleration control mechanism. A spindle-type positioner...
5186213 29  
An improved hydraulic servo-valve including a spool (10, 10R, 10L) adapted to slidably move in a valve body (1) to change the direction of flow of a working liquid and vary a flow rate of the...
5165448 Two-stage servovalve with compensatoin circuit to accommodate "dead zone" d u  
A two-stage flow-control electrohydraulic servovalve has a pilot-stage (14) and a second-stage valve spool (6) mounted for sliding movement relative to a body (1). The pilot-stage (14) is arranged...
5035254 Power transmission  
An electrohydraulic servovalve comprising a torque motor which receives an electrical signal and positions a flapper between a pair of opposed nozzles to control a spool valve and a feedback...
5027856 Electrohydraulic signal converter  
An electrohydraulic signal converter includes an armature which is movable in a magnetic field generated by field coils and is located between two inlet channel orifices that are provided with...
5027858 Multistage servovalves  
Two and three stage servovalves having a first stage comprising a torque-motor driven, double jet, flapper valve, extend the present art in dynamic response through the replacement of the present...
4938249 Chip tolerant flapper  
A reverse-flow fluid control system utilizes a pair of rivet-shaped flappers mounted on a motor driven lever to apportion fluid between a pair of nozzles. Each flapper is slideably mounted upon...
4922964 Servovalve construction  
A hydraulic servovalve including a torque motor and a valve housing containing a fluid inlet conduit in communication with a spool chamber, a spool within the spool chamber, a filter chamber...
4922963 Hydraulic servovalve  
A hydraulic servovalve including a valve body, a spool bore in the valve body, a spool in the spool bore, inlet and outlet conduits in the valve body, control conduits in the valve body, annular...
4907615 High frequency response servovalve with electrical position feedback element structure and method  
Electrohydraulic servovalve structure and method. The servovalve structure has minimum oil passage length and oil volume and a high response force motor with a light weight armature and a stiff...
4883091 Multi-port self-regulating proportional pressure control valve  
A multi-port, self-regulating, proportional control valve preferably uses a load output feedback system to produce working fluid load output pressures that are proportional to pilot control fluid...
4761575 Servo-valve and a control motor therefor  
A control motor for a servo-valve. Adjacent to the control coil of the control motor a dampening coil is located and short-circuited, so as to provide for an improvement of the frequency...
4705059 Electrofluidic transducer of the nozzle/plate type and hydraulic servo-valve equipped with such a transducer  
The transducer comprises a piezoelectric double-layer plate, the movements of which, under the effect of electrical signals, directly control the flow from one or two spray nozzles. The plate is...
4624284 Servovalve  
A servovalve includes a flow-control valve connectable between a source of fluid pressure and a load and having a spool displaceable between an open position permitting fluid flow between the load...
4623003 Hydraulically actuated spool valve  
A reduced drive area hydraulically actuated spool valve is protected against cavitation and provided with enhanced lubrication by connecting the variable volume inside the valve housing adjacent...
4617966 Electromagnetic positioner for a servovalve or the like  
An electromagnetic positioner for positioning the drive arm of a servovalve or the like, comprising an armature extending between laterally spaced pairs of vertically disposed and vertically...
4609012 Servo valve  
A housing has an inner area defined by end walls, side walls, a top wall, and a bottom wall having a flat inner surface. Inlet and outlet ports open through the flat inner surface. The inlet port...
4585029 Electro-hydraulic servo valve  
An electro-hydraulic servo valve of two-stage type including a beam mounted for swinging movement with respect to the casing of the valve. One portion of the beam is engaged with the second-stage...
4569272 Power transmission  
A hydraulic control system comprising a hydraulic actuator having opposed openings adapted to alternately function as inlets and outlets for moving the element of the actuator in opposite...
4538633 Optical-hydraulic control system  
An optical hydraulic control wherein the flow of hydraulic fluid is controlled by movement of a valve spool 12. Movement of the valve spool is initiated by a hydraulic pressure differential that...
4513782 Electrohydraulic servovalve device  
A servovalve device assembly is provided with an electronic matching circuit positioned upstream of the servovalve. The matching circuit supplies electric control signals whose purpose is to...
4492245 Nozzle and flapper with squeeze film damping  
An electro-hydraulic control structure having a control input positioning a flapper relative to a nozzle to generate a control output pressure is provided with a squeeze film damper which utilizes...
4456031 Electro-hydraulic servo valve system  
An electro-hydraulic servo valve system comprising a two-stage spool type servo valve including a first stage comprising an electrical force motor and a second stage including a spool for...
4352367 Electro-hydraulic control structure  
A motor-nozzle coupling member for coupling a motor to a nozzle in an electro-hydraulic control structure wherein a linear electric motor having an armature is located at a fixed distance relative...
4333498 Stepper motor actuated servovalve  
A servovalve of the type wherein changes in two primary control pressures, as determined by a primary stage valve, positions a secondary output control valve. The primary stage valve is in the...
4265272 Transient start-up eliminator for pressure piloted valve  
A control valve assembly (10) is provided for controlling a hydrostatic transmission including a fluid pump having a variable swashplate, a source of control fluid under pressure, and a servo...
4232517 Exhaust gas control actuator  
An exhaust gas control actuator wherein the feed of secondary air fed to an exhaust piping is controlled by an oxygen concentration detector disposed in the stream of exhaust gas of an internal...
4227443 Fail-fixed servovalve  
A fail-fixed servovalve is provided for use in a digital control system. The servovalve is comprised of a deflecting means which deflects a jet pipe in response to an electrical input signal....
4202249 Power steering mechanism control valve  
A steering control valve and worm nut centering device for a power steering booster mechanism control valve is provided comprising a flexure rod carried either by the double-acting piston member...
4080873 Servoactuator  
A servoactuator for stopping a ram in its existing position or retracting the ram at a fixed rate to a locked position.
4061155 Electrohydraulic control system  
The system includes a way valve of the type provided with a housing, fluid inflow and consumer ports in the housing, and at least one valve member movable in the valve housing for establishing...
4054154 Self monitoring redundant hydraeric control system  
A control system having a plurality of control channels each having its own source of system hydraeric fluid under pressure and each having a control valve and a monitor valve. A position...
4050476 Low noise hydraulic servo valve  
A fluid flow control valve which includes a body formed to define a chamber having inlet, outlet and actuating ports for supplying and receiving fluid to and from external hydraulic machinery to...
4038998 Fluid flow divider  
A fluid flow divider having a fluid input port with passages therefrom to fluid flow paths leading to respective output ports. Said paths pass via regions acting on either side of a member which...

Matches 1 - 50 out of 172 1 2 3 4 >