Electro-rheological control valve

DETAILED DESCRIPTION An object of this invention is the provision of an E-R hydraulic control valve that is efficient in terms of power consumption and has a fail-safe shut down operation in case of a power failure to the valve.
A more specific object of the invention is the provision of an E-R hydraulic control valve that does not require the application of power to the E-R fluid shut-off operating mode.
Briefly, this invention contemplates the provision of an E-R hydraulic control valve that has two or more surfaces that can be moved relatively to one another to adjust a flow orifice size while maintaining a control voltage gradient across the E-R fluid and to seat one surface against the other to shut off fluid flow.
Combining movable mechanical fluid flow elements with E-R fluid control allows initial tuning of the valve to a particular application by mechanical restriction of an orifice, and E-R operating control of the fluid.
Seating the mechanical surfaces provides a fail-safe shut-down mode.