Optical-hydraulic control system
AssigneeParker-Hannifin Corporation
InventorCurtis E. Stevens
Life of this patent
Estimating the term…
Abstract
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 is established by moving a control member 34 out of an equilibrium position. Movement of the control member from its equilibrium position is accomplished by illumination of a beam support structure 36 with an optical command signal. The control member 34 is returned to its equilibrium position after appropriate movement of a valve spool 12 by mechanical linkage between control member 34 and valve spool 12 or, alternatively, by modulation of the optical command signal.
Claims24
A servovalve having a valve spool that is controlled in response to differential pressure between two ports, said servovalve comprising:
- a valve body that includes at least two fluid ports that are respectively in communication with two fluid chambers;
- means for controlling relative fluid pressure in said fluid chambers by selectively controlling the fluid through said fluid ports;
- a thermally sensitive beam structure that is mechanically connected to said valve body and to said controlling means, said beam structure maintaining said controlling means with respect to said fluid ports in response to the thermal state of said beam structure;
- and
- optical means for selectively illuminating the thermally sensitive beam structure to control the location of said controlling means with respect to said fluid ports.
A servovalve that provides a differential pressure between two output ports in response to optical wavelength command signals, said servovalve comprising:
- a valve body that includes two differential output passageways that are in communication with the output ports;
- means for controlling fluid pressure in the output passageways by controlling the fluid flow through the ports;
- first and second thermally sensitive beams that are mechanically connected to said controlling means and to said valve body, said thermally sensitive beams supporting said controlling means with respect to the ports;
- and
- optical means for selectively illuminating at least one of the thermally sensitive beams with light energy to control fluid pressure at said output passageways by pivoting said controlling means on said thermally sensitive beams.
An optical control for hydraulic valves wherein the flow of fluid is controlled by the position of an internal valve spool, said control comprising:
- means for controlling the flow of hydraulic fluid, said control means having an equilibrium position where the valve spool is maintained in steady state condition, said control means being movable away from the equilibrium position to determine movement of the valve spool;
- a reference beam that is mechanically connected to said controlling means, said reference being responsive to variations in ambient temperature;
- a sensor beam that is mechanically connected to said controlling means, said sensor beam being responsive to variations in ambient temperature and also being responsive to light energy;
- an optical energy source;
- and
- means for guiding the optical energy from said energy source and illuminating the sensor beam to control the movement of said controlling means.
Dependencies are inferred from the claim text.